Contents

U-151' was originally one of seven Deutschland class U-boats designed to carry cargo between the United States and Germany in 1916. Five of the submarine freighters were converted into long-range cruiser U-boats (U-kreuzers) equipped with two 15 cm deck guns, including U-151 which was originally to have been named Oldenburg. They were the largest U-boats of World War I.

On 2 June 1918, known to some historians as "Black Sunday", U-151 sank six American ships and damaged two others off the coast of New Jersey in the space of a few hours. The next day the tankerHerbert L. Pratt struck a mine previously laid by U-151 in the area but was later salvaged. Thirteen people died in the seven sinkings, their deaths caused by a capsized lifeboat from SS Carolina.[4]

U-151 returned to Kiel on 20 July 1918 after a 94-day cruise in which she had covered a distance of 10,915 nmi (20,215 km; 12,561 mi). Her commander reported that she had sunk 23 ships totalling 61,000 tons and had laid mines responsible for the sinking of another four vessels.[8]